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Abstract:

The present disclosure relates to a tool gripper chain bendable in two
directions that has a chain assembly that includes: gripper blocks that
each have a first tooth at the center of a curved groove; first and
second gripper assemblies that have first and second gripper members
rotatably mounted on the rear of gripper blocks and grip a tool; first
and second outer links that are formed in an arc shape; first and second
inner links that are formed in an arc shape and disposed zigzag with
respect to first and second outer links between first outer link and
second outer link; and first and second collars that are disposed between
first inner link and second inner link, in which first gripper assembly
is disposed in front of second outer link, second gripper assembly is
disposed ahead of second inner ink, and a first shaft hole of first
gripper assembly and second shaft hole of second gripper assembly are
coaxially arranged, such that first and second gripper assemblies are
coupled by a first shaft or a second shaft.

Claims:

1. A tool gripper chain bendable in two directions, comprising: first and
second gripper assemblies for gripping a tool, each having a gripper
block having a first tooth at the center of a curved groove, and first
and second gripper members rotatably mounted on the rear of the gripper
block; and a chain assembly having first and second outer links, first
and second inner links disposed between the first outer link and the
second outer link in a zigzag manner with respect to the first and second
outer links, and first and second collars disposed between the first
inner link and the second inner link, wherein the first gripper assembly
is disposed in front of the second outer link, the second gripper
assembly is disposed in front of the second inner link, and a first
mounting hole of the first gripper assembly and a second mounting hole of
the second gripper assembly are coaxially arranged so as to be coupled by
a first shaft or a second shaft.

2. The tool gripper chain bendable in two directions according to claim
1, wherein: the gripper block each have first and second shaft holes; the
first gripper member is rotatably mounted about the first mounting hole
and has a first spring guide in its lower portion and a second tooth in
its upper portion; the second gripper member is rotatably mounted about
the second mounting hole, and has a second spring guide in its lower
portion and a third tooth in its upper portion; the first and second
gripper assemblies each have a guide block mounted on the rear of the
gripper block, distanced with a gap from the first gripper member at its
one side and in contact with the second gripper member at the other side;
and the first and second gripper assemblies each have a compression
spring mounted on the first spring guide and the second spring guide.

3. The tool gripper chain bendable in two directions according to claim
1, wherein the distance between outermost surfaces of the first gripper
member and the second gripper member is smaller than the distance between
the centers of the first mounting hole and the second mounting hole and
larger than the distance between the outer surfaces of the lower ends of
the first gripper member and the second gripper member.

4. The tool gripper chain bendable in two directions according to claim
1, wherein the angle made by the line connecting the centers of the first
mounting hole and the second mounting hole and the line from the first
mounting hole or the second mounting hole tangential to the upper end of
the first gripper member or the second gripper member is acute, and
wherein the angle made by the line connecting the centers of the first
mounting hole and the second mounting hole and the line from the first
mounting hole or the second mounting hole and tangential to the lower end
of the first gripper member or the second gripper member is acute.

5. The tool gripper chain bendable in two directions according to claim
1, wherein: the first outer link has first and second fastening holes at
both sides, and the second outer link has third and fourth fastening
holes at both sides; and the first and second inner links have fifth and
sixth fastening holes at both sides and seventh and eighth fastening
holes at both sides, respectively, wherein the first and second outer
links and the first and second inner links each are formed with a convex
lower portion.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a Section 371 National Stage Application of
International Application No. PCT/KR2009/006371, filed Nov. 2, 2009 and
published, not in English, as WO2010/056005 on May 20, 2010.

FIELD OF THE DISCLOSURE

[0002] The present disclosure relates to a tool gripper, and more
particularly, to a tool gripper chain that is installed at a tool
magazine of a machine tool and can be moved by operation of a driving
unit to a position where a specific tool among a plurality of tools
mounted and held on a gripper is removed.

BACKGROUND OF THE DISCLOSURE

[0003] In general machine tools, a plurality of tools is held in a tool
magazine and a specific tool is removed or mounted back by a command from
a controller.

[0004] Further, in the tool magazine, a gripper is disposed at one side of
a chain, the chain is engaged with a plurality of chain sprockets, such
that as the sprockets rotate, the chain moves to an automatic tool
changer (ATC) where a tool at a specific position is removed, or mounts a
tool sent from the ATC to the gripper of the chain.

[0005] However, each link constituting the chain is equipped with a
gripper in the chain of the related art, but the chain bends outward
only, not inward, when bending.

[0006] Since the chain cannot bend inward, any one gripper may interfere
with an adjacent gripper or the chain cannot smoothly come in contact to
the chain sprocket when bending backward.

[0007] Further, it is required to install more kinds of tools in order to
machine workpieces having various shapes, but since the chain of the
related art bends only outward in a convex shape, it is necessary to
design and manufacture the tool magazine in a large size in order to
increase the number of tools.

[0008] In particular, considering the size of the tool magazine and the
number of tools, the occupied space inefficiently increases, such that a
relatively small number of tools are necessarily disposed in a unit area.

[0009] The discussion above is merely provided for general background
information and is not intended to be used as an aid in determining the
scope of the claimed subject matter.

SUMMARY

[0010] The disclosed embodiments have been made in an effort to provide a
tool gripper chain bendable in two directions that makes it possible to
dispose a larger number of tools in a unit area than a chain of the
related art.

[0011] The technical problems are not limited to the foregoing technical
problems. Other technical problems, which are not described, can clearly
be understood by those skilled in the art from the following description.

[0012] This summary is provided to introduce a selection of concepts in a
simplified form that are further described below in the Detailed
Description. This Summary is not intended to identify key features or
essential features of the claimed subject matter, nor is it intended to
be used as an aid in determining the scope of the claimed subject matter.

[0013] An exemplary embodiment of the present disclosure provides a tool
gripper chain bendable in two directions having a chain assembly that
includes: gripper blocks that each have a first tooth at the center of a
curved groove; first and second gripper assemblies that have first and
second gripper members rotatably mounted on the rear of the gripper
blocks and grip a tool;

[0014] first and second outer links that are formed in an arc shape; first
and second inner links that are formed in an arc shape and disposed
zigzag with respect to the first and second outer links between the first
outer link and the second outer link; and first and second collars that
are disposed between the first inner link and the second inner link,

[0015] In which the first gripper assembly is disposed ahead of the second
outer link, the second gripper assembly is disposed ahead of the second
inner ink, and a first shaft hole of the first gripper assembly and a
second shaft hole of the second gripper assembly are coaxially arranged,
such that the first and second gripper assemblies are coupled by a first
shaft or a second shaft.

[0016] Further, the first and second gripper assemblies each include: a
gripper block that has the first tooth at the center of a curved groove,
the first and second shaft holes, which are symmetrical at the left and
right sides, and the first and second mounting holes at both sides
outside the first and second shaft holes; first gripper member that is
rotatably mounted in the first mounting hole and has a first spring guide
inside the lower portion and the second tooth inside the upper portion;
the second gripper member that is mounted on the second mounting hole,
opposite to the first gripper member, and has a second spring guide
inside the lower portion and the third tooth inside the upper portion; a
guide block that is mounted on the rear of the gripper block and has one
side with a gap from the first gripper member and the other side being in
contact with the second gripper member; and a compression spring that is
mounted on the first spring guide and the second spring guide and applies
restoring force in the expansion direction.

[0017] Further, the distance between the outermost sides of the first
gripper member and the second gripper member may be smaller than the
distance between the centers of the first mounting hole and the second
mounting hole and larger than the distance between the outer sides of the
lower ends of the first gripper member and the second gripper member.

[0018] Further, the angle made by a line connecting the centers of the
first mounting hole and the second mounting hole and a line from the
first mounting hole or the second mounting hole and tangential to the
lower end of the first gripper member or the second gripper member may be
acute, and the angle made by a line connecting the centers of the first
mounting hole and the second mounting hole and a line from the first
mounting hole or the second mounting hole and tangential to the lower end
of the first gripper member or the second gripper member may be acute.

[0019] Further, the chain assembly includes: first and second outer links
having the first and second fastening holes and the third and fourth
fastening holes at both sides, respectively; and first and second inner
links disposed zigzag with respect to the first and second outer links
inside the first outer link and the second inner link and having fifth
and sixth fastening holes and seventh and eighth fastening holes at both
sides, respectively, in which the first and second outer links and the
first and second inner links may be formed in a shape having a convex
lower portion and a space such that the first tooth protrudes, at the
center, when seen from the front.

[0020] The details of other embodiments are included in the detailed
specification and the drawings.

[0021] In a tool gripper chain according to a disclosed embodiment, which
has the configuration described above, the chain can bend in two
directions, such that the chain can be disposed zigzag and a more number
of tools can be mounted and held in a unit area.

DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 is an exemplary view illustrating an example of a tool
magazine equipped with a tool gripper chain bendable in two directions
according to a disclosed embodiment.

[0023] FIG. 2 is an exemplary view illustrating the tool gripper chain
bendable in two directions according to a disclosed embodiment.

[0024] FIGS. 3 and 4 are exemplary views showing gripper assemblies of the
tool gripper chain bendable in two directions according to a disclosed
embodiment, in which

[0025] FIG. 3 is a front perspective view and FIG. 4 is a rear perspective
view.

[0026]FIG. 5 is an exemplary exploded view illustrating the configuration
of a chain and the gripper assemblies in the tool gripper chain bendable
in two directions according to a disclosed embodiment.

[0027]FIG. 6 is an exemplary front view illustrating the configuration of
the chain and the gripper assemblies in the tool gripper chain bendable
in two directions according to a disclosed embodiment.

[0028]FIG. 7 is an exemplary view illustrating the operation of the tool
gripper chain bendable in two directions according to a disclosed
embodiment, that is, showing the front and the rear of an example when
the chain bends outward.

[0029] FIG. 8 is an exemplary view illustrating the operation of the tool
gripper chain bendable in two directions according to a disclosed
embodiment, that is, showing the front and the rear of an example when
the chain bends inward.

[0031] A tool gripper chain according to a disclosed embodiment has a
chain assembly 200 that includes: gripper blocks 120 that each have a
first tooth 123 at the center of a curved groove; first and second
gripper assemblies 110a and 110b that have first and second gripper
members 140a and 140b rotatably mounted on the rear of the gripper blocks
120 and grip a tool; first and second outer links 210 and 220 that are
formed in an arc shape; first and second inner links 230 and 240 that are
formed in an arc shape and disposed zigzag with respect to the first and
second outer links 210 and 220 between the first outer link 210 and the
second outer link 220; and first and second collars 250a and 250b that
are disposed between the first inner link 230 and the second inner link
240, in which the first gripper assembly 110a is disposed ahead of the
second outer link 220, the second gripper assembly 110b is disposed ahead
of the second inner ink 240, and a first shaft hole 122b of the first
gripper assembly 110a and the second shaft hole 122a of the second
gripper assembly 110b are coaxially arranged, such that the first and
second gripper assemblies 110a and 110b are coupled by a first shaft 260a
or a second shaft 260b.

[0032] Advantages and features of the disclosed embodiments and methods to
achieve them will be elucidated from exemplary embodiments described
below in detail with reference to the accompanying drawings.

[0033] Like reference numerals designate like components throughout the
specification.

[0034] A tool gripper chain bendable in two directions according to a
disclosed embodiment is described hereafter with reference to FIGS. 1 and
2.

[0035] FIG. 1 is an exemplary view illustrating an example of a tool
magazine equipped with a tool gripper chain bendable in two directions
according to a disclosed embodiment and FIG. 2 is an exemplary view
illustrating the tool gripper chain bendable in two directions according
to a disclosed embodiment.

[0036] As shown in FIG. 1, a tool gripper chain 100 bendable in two
directions according to a disclosed embodiment is mounted on a side of a
tool magazine 1 and a tool is mounted and held in the first and second
gripper assemblies 110a and 110b described below.

[0037] Further, as shown in FIGS. 1 and 2, the tool gripper chain bendable
in two directions according to a disclosed embodiment bends inward and
outward, such that the chain assembly 200 can bend zigzag, and first,
second, and third idle pulley 20, 41, or 60, a driving sprocket 12, or
the idle sprocket 50 is disposed at the bending portion and operates and
guides the chain assembly 200.

[0038] A process when the tool gripper chain 100 bendable in two
directions according to a disclosed embodiment passes is described in
more detail hereafter.

[0039] As shown in FIGS. 1 and 2, the tool magazine 1 includes, at a side,
a driving unit 10 that operates the chain assembly 200, the first idle
pulley 20 that guides the chain assembly 200, a manual gripper expander
30 that manually opens a specific gripper, a chain tension adjustor 40
that adjusts tension of the chain assembly 200, the idle sprocket 50 that
guides the chain assembly 200 that bends backward, and the third idle
pulley 60 that guides movement of the chain assembly 200, and a tool
locator 70 that locates and temporarily fixes the chain assembly 200 and
the gripper assemblies 100a and 100b at the position where a tool is
switched.

[0040] The driving unit 10 operates the chain assembly 200 by rotating the
driving sprocket 12 with a driving motor 11, in which the driving motor
rotates forward or backward in response to a command from a controller of
a machine tool and the amount of rotation is controlled such that
specific first and second gripper assemblies can reach the tool switch
position.

[0041] The manual gripper expander 30 is closed when a lever is pulled,
such that when the manual gripper expander 30 operates, with the first
and second gripper assemblies 110a and 110b within an operation range of
the manual gripper expander 30, a tool can be mounted or taken out by
hands in or from the first and second gripper assemblies 110a and 110b.

[0042] The chain tension adjustor 40 implemented by rotatably mounting the
second idle pulley 41 at the end portion of a guide bar that moves
straight, such that when the second idle pulley 41 is moved outward,
tension is applied and the chain assembly 200 is tightened, whereas when
the second idle pulley 41 is moved inward, tension exerted in the chain
assembly 200 decreases.

[0043] The idle sprocket 50 is installed without load and grooves 51 are
formed on the outer circumferential surface to be engaged with the chain
assembly 200.

[0044] The outer shape of the first, second, and third idle pulleys 20,
41, and 60 may be formed in a disc shape and a non-slip member 90 may be
disposed on the outer circumferential surface, and particularly, the
non-slip member 90 may be made of an elastic material, such that
noise/vibration can be absorbed/attenuated.

[0045] The tool locator 70 includes a pressing member 71 having a shape
corresponding to the chain assembly 200 and the pressing member 71 is
moved forward/backward by the operation of an actuator 72, such that when
the pressing member 71 moves forward, the chain assembly 200 is pushed
and located, whereas when the pressing member 71 moves backward, the
chain assembly 200 can freely move.

[0046] Hereafter, the configuration of the tool gripper chain 100 bendable
in two directions according to a disclosed embodiment is described in
more detail with reference to FIGS. 3 to 6.

[0047] FIGS. 3 and 4 are exemplary views showing the gripper assemblies of
the tool gripper chain bendable in two directions according to a
disclosed embodiment. FIG. 3 is a front perspective view, FIG. 4 is a
rear perspective view, FIG. 5 is an exemplary exploded view illustrating
the configuration of the chain and the gripper assemblies of the tool
gripper chain bendable in two directions according to a disclosed
embodiment, and FIG. 6 is an exemplary front view illustrating the
configuration of the chain and the gripper assemblies of the tool gripper
chain bendable in two directions according to a disclosed embodiment.

[0048] As shown in FIGS. 3 to 5, the tool gripper chain 100 can be largely
divided into the first and second gripper assemblies 110a and 110b and
the chain assembly 200.

[0049] The first and second gripper assemblies 110a and 110b each include
the gripper block 120 having the first tooth 123 at the upper center, the
first and second gripper members 140a and 140b rotatably coupled to the
rear of gripper block 120, and a compression spring 150 disposed under
the first and second gripper assemblies 140a and 140b and applying force
to close a second tooth 143a and a third tooth 143b that are formed at
the ends of the first and second gripper assemblies 140a and 140b.

[0050] Further, the chain assembly 200 includes first and second outer
links 210 and 220 formed in arc shapes, first and second inner links 230
and 240 formed in arc shapes and disposed zigzag with respect to the
first and second outer links 210 and 220 between the first outer link 210
and the second inner link 220, and first and second collars 250a and 250b
disposed between the first inner link 230 and the second inner link 240.

[0051] Further, the first gripper assembly 110a is disposed ahead of the
second outer link 220, the second gripper assembly 110b is disposed ahead
of the second inner link 240, and a first shaft hole 121a of the first
gripper assembly 110 and a second shaft hole 121b of the second gripper
assembly 110b are coaxially arranged, such that the first gripper
assembly 110a and the second gripper assembly 110b may be coupled by a
first shaft 260a and a second shaft 260b.

[0052] The configuration of the first and second gripper assemblies 110a
and 110b are described first in more detail.

[0053] The first and second gripper assemblies 110a and 110b may each
include: the gripper block 120 that has the first tooth 123 at the upper
center, the first and second shaft holes 121a and 121b, which are
symmetrical at the left and right sides, and the first and second
mounting holes 122a and 122b at both sides outside the first and second
shaft holes 121a and 121b; the first gripper assembly 140a that is
rotatably mounted in the first mounting hole 122a and has a first spring
guide 142a inside the lower portion and a second tooth 143a inside the
upper portion; the second gripper member 140b that is mounted on the
second mounting hole 122b, opposite to the first gripper member 140a, and
has a second spring guide 142b inside the lower portion and a third tooth
143b inside the upper portion; a guide block 130 that is mounted on the
rear of the gripper block 120 and has one side with a gap (t) from the
first gripper member 140a and the other side being in contact with the
second gripper member 140b; and the compression spring 150 that is
mounted on the first spring guide 142a and the second spring guide 142b
and applies restoring force in the expansion direction.

[0054] Further, as shown in FIG. 6, the distance L2 between the outermost
sides of the first gripper member 140a and the second gripper member 140b
may be smaller than the distance L1 between the centers of the first
mounting hole 122a and the second mounting hole 122b and larger than the
distance L3 between the outer sides of the lower ends of the first
gripper member 140a and the second gripper member 140b.

[0055] On the other hand, as shown in FIG. 6, the angle A11 or A12 made by
the line L1 connecting the centers of first mounting hole 122a and second
mounting hole 122b and the line L2 from the first mounting hole 122a or
the second mounting hole 122b and tangential to the lower end of the
first gripper member 140a or the second gripper member 140b may be acute
while the angle A21 and A22 made by the line L1 connecting the centers of
the first mounting hole 122a and the second mounting hole 122b and the
line L3 from the first mounting hole 122a or the second mounting hole
122b and tangential to the upper end of the first gripper member 143a or
the second gripper member 143b may be acute.

[0056] The configuration of the chain assembly 200 is described in more
detail hereafter.

[0057] The chain assembly includes first and second outer links 210 and
220 having first and second fastening holes 211 and 212 and third and
fourth fastening holes 221 and 222 at both sides, respectively, and first
and second inner links 230 and 240 disposed zigzag with respect to the
first and second outer links 210 and 220 inside the first outer link 210
and second outer link 220 and having fifth and sixth fastening holes 231
and 232 and seventh and eighth fastening holes 241 and 242 at both sides,
respectively, as shown in FIGS. 3 to 5.

[0058] In particular, the first and second outer links 210 and 220 and the
first and second inner links 230 and 240 may be formed in a shape having
a convex lower portion and a space such that the first tooth 123
protrudes, at the center, when seen from the front, as shown in FIG. 6.

[0059] Although portions of the first and second gripper assemblies 110a
and 110b and the chain assembly 200 were described above, the entire may
be combined, as shown in FIGS. 1 and 2, and portions of the first and
second gripper assemblies 110a and 110b and the chain assembly 200 may be
repetitively connected.

[0060] Hereafter, the operation of the tool gripper chain 100 bendable in
two directions 100 according to a disclosed embodiment is described.

[0061] First, the operation of the first and second gripper assemblies
110a and 110b is described with reference to FIGS. 3, 4, and 6.

[0062] The first and second gripper assemblies 110a and 110b grip a tool
and are engaged at three points by first, second, and third teeth 123,
143a, and 143b.

[0063] The tool is removed, when the second tooth 143a and the third tooth
143b of the first gripper member 140a and the second gripper member 140b
are opened, and when the tool is mounted, the closer the center of weight
of the tool to the center of the chain assembly 200, the more the tool
becomes stable.

[0064] That is, since the upper portions of the first and second outer
links 210 and 220 and the first and second inner links 230 and 240 are
depressed, they can avoid interference with the sink of the tool.

[0065] Further, since a first side 144a inside the first gripper member
140a has a guide block 130 and gap (t), the first gripper member 140a can
rotate within a predetermined range of angle, and since a second side
114, which is one side of the second gripper member 140b, is in contact
with the guide block 130, the second gripper member 140b can be prevented
from rotating.

[0066] That is, the first gripper member 140a can freely rotate within the
contact range with the guide block 130, while the second gripper member
140b can be fixed.

[0067] Further, the compressing spring 150 applies force such that the
second tooth 143a of the first gripper member 140a is kept toward the
third tooth 143b, such that the tool mounted on f the first and second
gripper assemblies 110a and 110b can be stably held, without unexpectedly
separating or falling.

[0068] Bending of the tool gripper chain 100 is described hereafter.

[0069]FIG. 7 is an exemplary view illustrating the operation of tool
gripper chain 100 bendable in two directions according to a disclosed
embodiment, in which the front and the rear are shown when the chain
bends outward, and FIG. 8 is an exemplary view illustrating the operation
of the tool gripper chain 100 bendable in two directions according to a
disclosed embodiment, in which the front and the rear are shown when the
chain bends inward.

[0070] The example when the chain bends outward is described first with
reference to FIG. 7.

[0071] When the chain assembly 200 bends, there is no interference between
the first gripper assembly 110 and adjacent the second gripper assembly
110b and the operation is described with reference to FIG. 6.

[0072] The first gripper assembly 110a and the second gripper assembly
110b always bends about the first shaft 260a or the second shaft 260b,
regardless of bending in any direction, that is, inward or outward.

[0073] As shown in detail in FIGS. 5 and 6, the first and second shafts
260a and 260b are inserted in the first and second mounting holes 122a
and 122b of the gripper block 130 and the distance L1 between the centers
of the first mounting hole 122a and the second mounting hole 122b is
larger than the distance L2 between the outermost sides of the first and
second gripper members 140a and 140b and also larger than the distance L3
between the outer sides of the lower ends of the first and second gripper
members 140a and 140b, such that the first gripper assembly 110a does not
interfere with the second gripper assembly 110b, when bending about the
first shaft 260a or the second shaft 260b.

[0074] Further, since the angle A11 or A12 made by the line L1 connecting
the centers of first mounting hole 122a and second mounting hole 122b and
the line L2 from the center of the first mounting hole 122a or the second
mounting hole 122b and tangential to the lower end of the first gripper
member 140a or the second gripper member 140b is acute while the angle
A21 or A22 made by the line L1 connecting the centers of the first
mounting hole 122a and the second mounting hole 122b and the line L3 from
the center of the first mounting hole 122a or the second mounting hole
122b and tangential to the upper end of the first gripper member 140a or
the second gripper member 140b is acute, a sufficient space where the
first gripper assembly 110a and the second gripper assembly 110 can bend
is ensured, such that they can bend about the first shaft 260a or the
second shaft 260b, without interference.

[0075]FIG. 7 shows an example of bending with the inside narrow and the
outside wide, in which (a) of FIG. 7 is a front view and (b) of FIG. 7 is
a rear view.

[0076] In particular, as shown in (b) of FIG. 7, the first and third idle
pulleys 20 and 60 or the second idle pulley 41 is inserted between the
first and second inner links 230 and 240, in which the convex portions of
the first and second inner links 230 and 240 are guided on the first and
second pulleys 20 and 60, such that the chain assembly 200 can be
prevented from separating.

[0077] Further, the first and second columns 250a and 250b are in contact
with the outer circumferential surfaces of the first, second, and third
pulley 20, 41, and 60 and a non-slip member 90 is disposed on the outer
circumferential surfaces, such that non-slip member 90 absorbs shock and
noise.

[0078] On the other hand, as shown in FIG. 8, bending may be achieved,
with the second and third teeth 143a and 143b inside and the compressing
spring 150 outside.

[0079] The guide may be achieved by the first, second, and third idle
pulleys 20, 41, and 60, or the idle sprocket 50, as shown in FIG. 8.

[0080] Further, as shown in FIGS. 1 and 2, it may be pulled by the driving
sprocket 12.

[0081] The driving sprocket 12 or the idle sprocket 50 has a groove 51 on
the outer circumferential surface and the first and second collars 250a
and 250b are inserted in the grooves 51.

[0082] As described above, since the tool gripper chain 100 according to a
disclosed embodiment can bend inward or outward, the chain assembly can
smoothly move, even if the chain assembly is disposed zigzag.

[0083] Therefore, the length of the chain may be further increased and a
more number of gripper assemblies may be mounted on the chain, such that
a more number of tools can be mounted and held.

[0084] Although exemplary embodiments have been described above with
reference to the drawings, it will be understood to those skilled in the
art that the present invention may be implemented in various ways without
changing the spirit of necessary features of the present invention.

[0085] Therefore, the embodiments described above should be construed as
being exemplified and not limiting the present invention, the scope of
the present invention is characterized by the detailed description of the
following claims, and all changes and modifications from the meaning,
range, and equivalent concept of claims should be construed as being
included in the present invention.

[0086] A tool gripper chain according to a disclosed embodiment can be
used for machine tools that are required to mount and hold various types
of tools.